From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from SJ2PR03CU001.outbound.protection.outlook.com (mail-westusazon11022074.outbound.protection.outlook.com [52.101.43.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7276D30DD33 for ; Thu, 18 Sep 2025 15:50:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.43.74 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758210610; cv=fail; b=e8tswMC5OkB1eHFd2q5xDPVefddqFm8iwYKlE7rE+QCBrvlqFo60YJGRWRcmbZltPZ8LhbrjPINevj0W+9PEXwjCk/k6Z6skfFJl/yWpbv9uKC1gNoyFs76Se/pQMMR++i51KzqYU7fLLtR950or4aOqJtiJLd1dkzxag0zY4h4= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758210610; c=relaxed/simple; bh=7MMj8MR7j+pVE3saGGDQXXXEbor5KTBYFvJlgdxa/lI=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=rbYMurj0J7SCZvkWjjPDQZ/hz+AJHZvOAu1LIwJROCQvDHpmcsbTDMwtiz+uzsd9FwEA1Tdsu6RgUB31KAQf3HJL8oLBZXvFJZRaU9Tc5MaOrVHlvqAateCKpYV/HHw0mJl2dN5cGabihDez84bDECO7z+o1Bgqk+YhkEuNmZws= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=os.amperecomputing.com; spf=pass smtp.mailfrom=os.amperecomputing.com; dkim=pass (1024-bit key) header.d=os.amperecomputing.com header.i=@os.amperecomputing.com header.b=lw+2csNx; arc=fail smtp.client-ip=52.101.43.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=os.amperecomputing.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=os.amperecomputing.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=os.amperecomputing.com header.i=@os.amperecomputing.com header.b="lw+2csNx" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=ErieL/+HvJMyZnpnmr29007gVaKx9SwrCBOCzrZCPBV5hUASI/eDKHOHMtP73QbTPdVffA78lo+E2bnv7y25uqZidD77PBGdx/WGvKhKO2YLF2rxSzrcZ9JESlc125AiVhXUI5P12sz1bJwt+g1MeOsilEa3ZGQnwm7X55VmDR+dvUpMuIMXeS4l756fMenVQxyGQr5dUq+9nYhqniQRa+3+pJ/v6Td9w2NmEg/lsEuEAencFtl4SgN7Tyc8p81DOguAim8lSU9mTErRlGTmQ6AMUUNtqJPkiRDtB9o7d8lhRGHdNLe5UzhQarTJBN9BCLP/ZIfjP+euRuaMkg/HWg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=6iJgEA0z8IK2eMIQvuiTiZpDwyYYIkVtWtaC66G5RYc=; b=gRzuvH1sXRzTb/5+DSXsXZu6ktB44fgzYBMjhj31NBoafs6NMBkGvOUhHSjmnSYoYiRPPp1zdEuaxGl7CoZ/u+0h9a9+G5mH78RBXTmZdj/PYLo9DV7/TkjChtj2CBpIKmWUvEP97PfICx0xCBlSfgTMEj2WqEmfmunJ2b3c+outUhBYVUxjtT09ZfPtbLFVjAePj/KLF2LoXVlkMc3oWLqTE6hYbNWQ048wIFm6L+fL+87C1z2a9bU7odou8ERYdu5rxPEdtxHUXuFclX2OmsDLJkzK2lhr6LbDdqZIsVmg47RZp8KF0qBFdqeeNCebvNRtfCYXr7uySBFXOPIVMw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=os.amperecomputing.com; dmarc=pass action=none header.from=os.amperecomputing.com; dkim=pass header.d=os.amperecomputing.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=os.amperecomputing.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=6iJgEA0z8IK2eMIQvuiTiZpDwyYYIkVtWtaC66G5RYc=; b=lw+2csNxYZ1b3fFZ6iIKcYFdmlqGq/ZQZKsB+sldzscydNMTWirDxtkEEX83pV5K2iIB9Zx5nRZMUZGdA/j0vi0K19q9zp2ESoq6/eqtC9bhSbSpFNOXqVt76MQNygm9XzfpO5QsVCJNj1mkqan3KO6ad857dllsU59MAgfMyEM= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=os.amperecomputing.com; Received: from CH0PR01MB6873.prod.exchangelabs.com (2603:10b6:610:112::22) by PH0PR01MB6699.prod.exchangelabs.com (2603:10b6:510:74::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9137.14; Thu, 18 Sep 2025 15:50:05 +0000 Received: from CH0PR01MB6873.prod.exchangelabs.com ([fe80::3850:9112:f3bf:6460]) by CH0PR01MB6873.prod.exchangelabs.com ([fe80::3850:9112:f3bf:6460%3]) with mapi id 15.20.9137.012; Thu, 18 Sep 2025 15:50:05 +0000 Message-ID: <2f03eb8f-f343-4243-bd87-9b9c15d00beb@os.amperecomputing.com> Date: Thu, 18 Sep 2025 08:50:02 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 5/5] arm64: kprobes: call set_memory_rox() for kprobe page To: Ryan Roberts , Catalin Marinas Cc: will@kernel.org, akpm@linux-foundation.org, david@redhat.com, lorenzo.stoakes@oracle.com, ardb@kernel.org, dev.jain@arm.com, scott@os.amperecomputing.com, cl@gentwo.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20250917190323.3828347-1-yang@os.amperecomputing.com> <20250917190323.3828347-6-yang@os.amperecomputing.com> <22732cbe-20f8-4d1e-b086-e34d0f9bbb35@os.amperecomputing.com> <960fbbba-8018-4e42-b1fd-6ed96c148007@arm.com> Content-Language: en-US From: Yang Shi In-Reply-To: <960fbbba-8018-4e42-b1fd-6ed96c148007@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: BY5PR17CA0020.namprd17.prod.outlook.com (2603:10b6:a03:1b8::33) To CH0PR01MB6873.prod.exchangelabs.com (2603:10b6:610:112::22) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH0PR01MB6873:EE_|PH0PR01MB6699:EE_ X-MS-Office365-Filtering-Correlation-Id: dc15db0e-16f5-456a-a653-08ddf6cb0985 X-MS-Exchange-AtpMessageProperties: SA X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|7416014|376014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?QlhyWE5lK0pFZTJ3V2xwVmhTaG1MT3poNWdab1ArN08rMkNiM0Nyd056TVh5?= =?utf-8?B?UHhEa1h0ZlBoRXdpeXBLMmhFUzlRTDBSTjdHOHNQWTUxVGdubmVWMm4yUUp4?= =?utf-8?B?TnJ5T0NDTXQ4bDFyWTBwTjhnNWVYcnJNMmVEdUV5aXFQZHpIUW5pK1YvdEkx?= =?utf-8?B?elJzR1oxM1o2cTU1TE1MK1hyblNpQlRFMXFVRHF0c3lBQjl1WFVGYURRRjg2?= =?utf-8?B?VVAvdC90dzlkVHE1UElqdStHL1U3MjNQdVN2MWJxbEt5eE96cWlUWFB0UnBu?= =?utf-8?B?ak9sUTFKOERkc2RGTTNjUjl1eEJtSEo4czMvMGFaa3pYbGlWd0RhdXo1aVpB?= =?utf-8?B?YjAvSjJVcVBCVHl4UUZUUmhDTElIbVlOMlZpd3h6YkxPdGZ4OExPdmh5YjRI?= =?utf-8?B?Z1NqcVJyeWxKRnlYR01sQmxkKy9pM0dyUGdMbkJob2dhZUV0anJUTUt3cVRp?= =?utf-8?B?RVFkc2N2NWc0eVZoMnVMcTRZU2hCSWwzWEJ0blZnMzhHdFFWWGdydHlxSXBZ?= =?utf-8?B?cjRYSWk3U0tabzlxUENPUTBuSFVHdnBKL3Z6VkRSMEtHTVBPMXg2TVhnaXJt?= =?utf-8?B?eXRXNVQrWXN2cmhPeE4xLzM5KzhVcDNlT1hPRWJoZ1BKOWtGcHVybXBhM2JB?= =?utf-8?B?dHd3d1NqNE1ESzZuYkhmMWRpZFNtRXhCc3h3WFlaY1l2SUg2SHBwbDFtemUx?= =?utf-8?B?UE5Td1BRak1aQU5WejVRZUI3dkZkdWNYeWdYL0J6V1RCSW9PNk1tbDJuSllO?= =?utf-8?B?YTdnU1BpWndXZzZndmo2VXY2eVNyc3NJS1RQMzBTelE0dFQ0UzFlV3pLSmRZ?= =?utf-8?B?VjdWZXZNZjZUcDR4eUtsM000eWMxbjEyZmNFUEw0RVJnUWI3VDFBWkNTeE9E?= =?utf-8?B?M2ZvTTRXbWpuR0hnSFFRRVhjeng2WmNkRm5CVFhTVDB6TW1qbVZEVDkzbnVD?= =?utf-8?B?UlRFaDFvSERzMkZ4YmFRREJvaHRwUWw2aGFVWVo0S3diQzZ4c2JvbmFoZmFz?= =?utf-8?B?NDdFSFR0b3J3YnpvWVA1TVVxL1EwWjdEckJRbjlBcUlYbEZKbEZ0eDd5bnpz?= =?utf-8?B?eTN4RkxTWGc0RTZBRUpzYkpobENXZVBkV09LbVU1c2RpTmwxQVdNcUQrTWw1?= =?utf-8?B?TWI4V1F5c0NkMm0vUnVWUHNrR2xGZlk1ZzhzdTlZS1NOampWNWl0NlJnVkc0?= =?utf-8?B?ZnNpeHpXQjhqem9DdVRiT3RjMlY4TGszMFVRTnZKekQvdnpHWTdVWi9XV0Jj?= =?utf-8?B?aitJcnNVU3FrRk1kTHYzSG40NVpyMEoyaHRwdks1dERZbEpMeGJibDJZanMw?= =?utf-8?B?cElMWVBoN1NhK20vSzY0VkpFL3RIWkhwSHBzamVIQVBBc1JtMzVwSjVDRVdP?= =?utf-8?B?Y2JKWWdFeFRPYmNXNU5xaW5OOVV1L0tjdi9sN2ZhQTVyMExlTHI3OVU2OXcv?= =?utf-8?B?aUZwcGhVUEpsa09TczhDdWIyVW5ZamRKT2ZrTmF6QW5TdXAwWExGbmt1TzF3?= =?utf-8?B?aWY0OS9Dc0hSS1Q1WWxkRW4yVFJack1pZ3pQTkhSVytIZCtuYzNSSVlSeVNP?= =?utf-8?B?QVBpQXpnNG1vY3hSVXhoSEtCMGpzRjdibXZPOGM3ekV1RW5pemtCVENndFdj?= =?utf-8?B?L0JKYTdUYmVHdXJpeGduZXRVSUxHbXJoaGxuak1vR2xWcFVXL1ljRUIzTFhK?= =?utf-8?B?OUU3NU1hSGVSeXNvRkVpNUp3L1VHMDlqKzl2ZGpnejRROHlNbnV5UGtlNHMy?= =?utf-8?B?Q1VvMHpUVnZmb2JNRTlEMHp5TjNOQnEyWWdiNmVIWWVObnN6NGJaNGNqbGtp?= =?utf-8?B?MDlxR1FDYjA1SDhLZjdiaDJ5RkJvVGRzRmdLb1hmWlB4T1FJbWdSRnJ0cEI0?= =?utf-8?B?TWw4dVdSL0VxMCt4cWlLUVZtOFpuaGdGQlNicjZtZitCeGFmbXJKanQ3REkv?= =?utf-8?Q?JupioRQ4ig0=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH0PR01MB6873.prod.exchangelabs.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(7416014)(376014);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ZFdtK0wxT0xuT25RM0hvZXRQem84N2Fwd05LQmthQmk3T08waUE5MngwQjlR?= =?utf-8?B?c1o0b1pzK2dsdFhBenlsNjBmb1VGSHl3akxWVTRXOVN5RlFBU0lOUVRaQUQr?= =?utf-8?B?bnVTYVZlZHRZMFJDZndYOGdLa2pSckZXNTV3a0tQZmJYTm93WGhqbWNjZVRM?= =?utf-8?B?Nm1oeSt2MUdnYno0L1I0SXpwVk5Pd3Z5RkpGYjErVEVZMUJOR3FGaVh6c3Jr?= =?utf-8?B?RzhCM29CaVFmUFJFK29UNGdzYm5RT0k3S3JaNFRHV1JoWElCVkNac1I1cXhy?= =?utf-8?B?aDdDczNyZmJ4b2l0cUhxeUhveGpmcElVZ3JvUU9BVSt6MEtVVTBNQ3RSSWc0?= =?utf-8?B?YXpCbE9QOEREaDAwQnlYSDcrbFpzZE9DNmU2aVBTNFVrNm95RHBPakdKeCtL?= =?utf-8?B?NlgzUTMwZWJJL25YcVlMT2NaRXJXZWRYTDBkdm54ZDdBcmVxMkRsYkt6Vjly?= =?utf-8?B?cXhkZ1hrOXRqa1FkU0trb0JqNG41c1FCZ21tZlVYVjBMNlJCemY0M2c2VU9p?= =?utf-8?B?Z0pVU2hib2xaR3VGamtLNnRRRmtpS2lERHJ6OGZYU3JweGM3d2ozOWV2Qjl0?= =?utf-8?B?VWxPME5CSUl5UTFtM3R3U0F3ZXpqdGZKaS85b0dWaDZkQUpHcTBIVjRYQVJh?= =?utf-8?B?NVpZK0tRQnRrODRITXgvcUo1WE1SRlREU1JUZGtLS2VGc0NwbSthbTZ1d1pB?= =?utf-8?B?UXZ1dnp3WjZsUmtlODg5SjlOQ0duZUdQdU9sS0xlL3JhekFxWHBKQjhwY0hl?= =?utf-8?B?TDdLUzc3ZjdIeUhUQmJjSE9ydnlOWHZHYUVWZEY5Ky80TXJmUWh0STdldFJW?= =?utf-8?B?Rll5WmlWc1RraTBIcjRFdkFZeG5pdW9Lc2VHVmw4ODU3UU11NXNIb3NlclR4?= =?utf-8?B?NnFVNGd2a2gvbnlJVndwTk5QOHp5eUNtYlVXODAzR3pMSXhhaW5JS0NzSmxi?= =?utf-8?B?NmhmWXNzOVJGNFVHOXh0NkFzRm82VmhqRDg3THJJMitVYVZLZUtyMHBCY2ZQ?= =?utf-8?B?b1NTYVZmakpBUDZLUHRuU1J6QkVsMHBSYVpYSU9kcThRZjdzSENVUVY0Rjlz?= =?utf-8?B?SE0ySDhmVFU4NkxzZHE4U1dITGVaK3RmM25aUVd2dWs4aTR0ZW5zS05TcW9p?= =?utf-8?B?d0dlZS9NNUpNUURkOW1sTFBDdkNJK0l6WWhjcFoxNlVweXF1dVBuR0YyU0R3?= =?utf-8?B?WU9JaFBtdWN6QmpFMWJ5TE8vRUo3aGxFSGl2OUN3Vm1JOVJVVU1UamlHMnNJ?= =?utf-8?B?M1lOYWZWZmF2Z0owcUE3VEl1Y2x1aUxtMHVCbEVaZFlZVWZhTFZETm1ob2FJ?= =?utf-8?B?NTIvL1BFa1Q3VkViMDBWUDVCRHRXbkFBUk5LVjUxdTBqSkFoc3JiOGVUc2Np?= =?utf-8?B?UHZNa055aERVM1hzZitEcEpuY0ZpVnlERmdBV3RJU2dwMkxvM0dENkU5aEgw?= =?utf-8?B?NXlQa3hRRUJBUkZLQzVaN2Z6MkRicjlKdzc2RWtLcjVyYkpSZ0MxMnBnVXdm?= =?utf-8?B?Z3p0RUwyeENEU2wwS3BkMU5DRU9nSFZMMUxZUzBhWGFidWZ0QUdqUzJ3Z05n?= =?utf-8?B?MFhaZVZEZkdWSmQxdGwrM3dFZ256M2VHTnZWZkVuZ3d4Smo2WnRKRWpGMXJk?= =?utf-8?B?d3BLSklEdWlBSEMzcGxiR295bFY4a0hhVEt5Z3J4cFc0cWR2NlFBL0ZaQUxw?= =?utf-8?B?MUlRNmdIQzNackNkallkdXNFbXhlNy9tM2Z1T0dBSUFJRDBpUUU0ZkNjOFdF?= =?utf-8?B?OGFrVm9yOGNPdnpER1Fzb1BVV0crQ1oxWlIyWGJRRnh2Q0R1WXlSeHZqYkow?= =?utf-8?B?Z1NhSkNnNmJ2TW84Tk9QcGliTVYvNE93MEZBRkcwQ0JrVkVEbDFpcmY1VzdG?= =?utf-8?B?eVljZzlQNlpOZ1VWMEc1WENlMGxaQ3JEVitCd2lBNzZJTTRtMDRua2ZaU2xO?= =?utf-8?B?NytVeDNiM0k5TE5vS3VNTTB4cE5aeGowV1hNd3lLdDByU202TDFhN21JNkZ3?= =?utf-8?B?Z3VwSjBMNnkzWjhUbVV2cDVjM3dxbms2dldoUGczYXMxMDdwdWR2dWhIc2Zy?= =?utf-8?B?NHU0QjFnUStEMkdNalpoNXFLWUNESFc3d0ZZVmNNT2NoWFZ0ZTJKdzV3VHJB?= =?utf-8?B?cm5JdmVmb2hqYTVIUXFLaWk1eVpPZXZpRGhFUm1QeHcyTXhCeFdodXFnN1Bk?= =?utf-8?Q?KUIZbj+NgJZro2ifZo3Zd+Q=3D?= X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: dc15db0e-16f5-456a-a653-08ddf6cb0985 X-MS-Exchange-CrossTenant-AuthSource: CH0PR01MB6873.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Sep 2025 15:50:05.8002 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5SxldrxMEZ3HHLO2jBvYds5iJnAu5ClInSZKqr4f9RBV/NnFrvKxZZU4jUNcJmdXPyo8lwhX4ETB1mot7P0eUdLS16bo3tcdZW5HvPsWCDY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR01MB6699 On 9/18/25 8:30 AM, Ryan Roberts wrote: > On 18/09/2025 16:05, Yang Shi wrote: >> >> On 9/18/25 5:48 AM, Catalin Marinas wrote: >>> On Wed, Sep 17, 2025 at 12:02:11PM -0700, Yang Shi wrote: >>>> The kprobe page is allocated by execmem allocator with ROX permission. >>>> It needs to call set_memory_rox() to set proper permission for the >>>> direct map too. It was missed. >>>> >>>> And the set_memory_rox() guarantees the direct map will be split if it >>>> needs so that set_direct_map calls in vfree() won't fail. >>>> >>>> Fixes: 10d5e97c1bf8 ("arm64: use PAGE_KERNEL_ROX directly in alloc_insn_page") >>>> Signed-off-by: Yang Shi >>>> --- >>>>   arch/arm64/kernel/probes/kprobes.c | 12 ++++++++++++ >>>>   1 file changed, 12 insertions(+) >>>> >>>> diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/ >>>> kprobes.c >>>> index 0c5d408afd95..c4f8c4750f1e 100644 >>>> --- a/arch/arm64/kernel/probes/kprobes.c >>>> +++ b/arch/arm64/kernel/probes/kprobes.c >>>> @@ -10,6 +10,7 @@ >>>>     #define pr_fmt(fmt) "kprobes: " fmt >>>>   +#include >>>>   #include >>>>   #include >>>>   #include >>>> @@ -41,6 +42,17 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); >>>>   static void __kprobes >>>>   post_kprobe_handler(struct kprobe *, struct kprobe_ctlblk *, struct pt_regs >>>> *); >>>>   +void *alloc_insn_page(void) >>>> +{ >>>> +    void *page; >>> Nit: I'd call this 'addr'. 'page' makes me think of a struct page. >> Sure. >> >>>> + >>>> +    page = execmem_alloc(EXECMEM_KPROBES, PAGE_SIZE); >>>> +    if (!page) >>>> +        return NULL; >>>> +    set_memory_rox((unsigned long)page, 1); >>> It's unfortunate that we change the attributes of the ROX vmap first to >>> RO, then to back to ROX so that we get the linear map changed. Maybe >>> factor out some of the code in change_memory_common() to only change the >>> linear map. >> I want to make sure I understand you correctly, you meant set_memory_rox() >> should do: >> >> change linear map to RO (call a new helper, for example, set_direct_map_ro()) >> change vmap to ROX (call change_memory_common()) >> >> Is it correct? >> >> If so set_memory_ro() should do the similar thing. >> >> And I think we should have the cleanup patch separate from this bug fix patch >> because the bug fix patch should be applied to -stable release too. Keeping it >> simpler makes the backport easier. >> >> Shall I squash the cleanup patch into patch #1? > > Personally I think we should drop this patch from the series and handle it > separately. > > We worked out that the requirement is to either never call set_memory_*() or to > call set_memory_*() for the entire vmalloc'ed range prior to optionally calling > set_memory_*() for a sub-range in order to guarrantee vm_reset_perms() works > correctly. > > Given this is only allocating a single page, it is impossible to call > set_memory_*() for a sub-range. So the requirement is met. > > I agree it looks odd/wrong to have different permissions in the linear map vs > the vmap but that is an orthogonal bug that can be fixed separately. > > What do you think? Yeah, sounds good to me. Thanks, Yang > > Thanks, > Ryan > > >> Thanks, >> Yang >> >>> Otherwise it looks fine. >>>